COMBI supplying low pressure domestic hot water.

[--tom]

Given a COMBI in a bungalow, supplying domestic hot water and the H/W outlet on the COMBI is only 15mm yet the 15m pipe is expected to supply a kitchen sink, a W/M, a separate WC and basin, a bathroom with a basin and W/C and a bath , and a seperate shower compartment with a mixer shower.
The hot water pressure at the basins and the shower is very poor and is even worse when two fixtures are on at the same time.
Any comments or suggestions?

 

[Agile]

You clearly do not understand how the boiler operates!

You dont say what make or model it is but its probably a 24 kW which heats 9.3 litres per minute by 35*C temperature increase.

That flow can operate your shower, basin, bath, kitchen sink, WMC, dish washer and any other outlet in the building as long as the total flow does not exceed 9.3 litres per minute.

Have you actually measured the flow?

Tony Glazier